After three years of worrying about respiratory viruses such as COVID and RSV, an old bug is making a new surge.
Norovirus cases are surging at a time of year when they're usually tapering off. According to the Centers for Disease Control and Prevention, positive norovirus tests on average exceeded 15% over a three-week period that ended last week.
The virus, which causes vomiting and diarrhea, is most serious in young children, the elderly and people with compromised immunity. And it’s contagious.
Dr. Peter Chin Hong, infectious disease specialist with UCSF, says the virus spreads rather easily.
"Whenever you get crowded and you didn’t get something for a few years, you’re going to get a little bit lower immunity, and it’ll be easier to catch," Chin Hong said. "And the more people that have it, the easier it is to catch."
Chin Hong advises not sharing utensils or towels with a sick person. And he notes that alcohol-based hand sanitizers don’t work against norovirus. He says you actually have to wash your hands with soap and water.
Those who contract norovirus can be contagious as long as two weeks, he added.
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